Design and implementation of a direct-connected 11 kV power conditioner

Implementations of direct connected high-voltage AC shunt power conditioners have focused on fundamental frequency power control, while other control objectives such as harmonic compensation have not been exercised. This paper demonstrates the multi-functional capability of a prototype direct-connected, high-voltage (11 kV) power conditioner. The prototype is based on a 3-level inverter topology and uses a series connection of eight IGBTs for each switching element in the 3-phase inverter. Laboratory testing confirms that the unit can perform all of the proposed functions, namely harmonic compensation, ripple control signal injection, and VAr control.